Our current research focuses on the area of adhesion molecules of immunoglobulin superfamily, CD200 that has been proposed to exist on neurons and down-regulate microglial functions in quiescent or activated status through the interaction of CD200 with CD200 receptors (CD200R); the latter supposed to be expressed on microglia. So far, no direct and convincing morphological evidence shows the existence of CD200R on resting microglia, in particular those in the intact/normal CNS. One purpose of research conducted in our lab is to test the possibility of abovementioned theory. CD200 is well known to effectively suppress immune activity of myeloid cells in anatomically diverse locations including the CNS. CD200 is also expressed by a broad range of tissues and cell types such as lymphoid cells and endothelium in addition to CNS neurons. Besides its known expression in nerve cells and fibers, we have recently shown CD200 distribution in Schwann cells enwrapping different types of nerve fibers, satellite glial cells of the sensory and autonomic ganglia and enteric glial cells. The immune suppressive CD200 seems to be a specific marker shared by the PNS glial cells that may exert a common immunomodulatory function in the PNS.

Our laboratory's research efforts are now concentrated on systemically analyzing CD200 distributions at the CNS and other possible epithelial cell elements outside the CNS. Using molecular biological methods and immunoelectron microscopic examination, we have recently found and published a heterogeneous distribution and novel LPS regulation of CD200 on vascular endothelium especially those in lung tissues. Although CD200 is not a novel molecule, it has drawn a great attention by many researchers in the past decade. Our aim in future would be to investigate and publish more results on CD200 in different body tissues. For example, we have recently found a novel distribution of CD200 that is associated with the myoepithelial cells in the salivary, mammary and sweat glands. Interestingly, it is also localized on the satellite glia in the dorsal root ganglion and Schwann cells in the peripheral nerves. We aim to determine the possible functions of CD200 on these cells.